Flow stopping apparatus for gas mains



Feb. 6,- 1962 v. E. ANKARLO FLOW STOPPING APPARATUS FOR GAS MAINS Filed pril 6, 1959 2 Sheets-Sheet 1 IN VEN TOR.

By WCTOREANKARLO.

TTORNEY Feb. 6, 1962 v. E. ANKARLO 9.

FLOW STOPPING APPARATUS FOR GAS MAINS 2 Sheets-Sheet 2 Filed April 6. 1959 4 :IIIII J5 INVENTOR. VICTOR EAN/(ARLO BY v ATTORNEY hce,

3,019,819 FLOW STOPPlNG APPARATUS FOR GAS MAINS Victor E. Ankarlo, 422 E. 1st St., Duluth, Minn. Filed Apr. 6, 1959, Ser. No. 804,320 Claims. (Cl. 138-93) This invention relates to flow stopping apparatus for gas mains.

. In my United States Patent 2,327,615, issued August 24, 1943, there is disclosed a gas main stopping or plugging apparatus including a stopping device which is laterally insertible, when in a collapsed condition, into a gas main or pipe and is then expanded into sealing engagement with the inner walls. of the gas main to block the flow of gas. After repairs or other operations are effected on the main, the stopping device is collapsed and laterally withdrawn from the main.

An object of the invention is to provide improvements on the general type of stopping apparatus disclosed in my above mentioned United States Patent 2,327,615 to the end of facilitating manipulation of the apparatus, promoting safety in use, enhancing the sealing action, withstanding rough treatment, and simplifying construction.

Another object is to provide a gas main stopping device which after lateral insertion into the gas main can be easily and quickly expanded into sealing engagement with the inner walls of the main, so as to minimize escape of gas.

Still another object is-to provide a gas main stopping apparatus including improved inflation means and control valve means. 7

I The invention further consists in the several features hereinafter described and claimed.

In the accompanying drawings,

FIG. 1 is a fragmentary longitudinal vertical sectional view of a gas main, showing flow stopping apparatus of the invention in operative position with respect thereto;

FIG. 2 is a similar view of the gas main, showing a contracted or collapsed stopping device thereof as it appears during insertion into and removal from the main;

FIG. 3 is a fragmentary sectional view of the applied I stopping device, taken generally on the line 3-3 of FIG.

1, and indicating the application of gas pressure to the device;

FIG. 4 is a longitudinal sectional view of a control valve assembly of the apparatus;

FIG. 5 is a detail view of a manipulating rod for the stopping device;

FIG. 6 is a perspective view of a stopper diaphragm in its detached condition, parts being broken away and parts being shown in section;

FIG. 7 is a transverse sectional view taken generally on the line 77 of FIG. 1, parts of the expanded stopping device being broken away and parts being shown in section;

I FIG. 8 1s a transverse sectional view taken on the lme 8-8 of FIG. 7;

FIG. 9 is a rear elevational view of the collapsed stopping device;

FIG. 10 is a fragmentary front elevational view of the collapsed stopping device;

FIG. 11 is a top view of the collapsed stopping device;

FIG. 12 is a longitudinal sectional view of the collapsed stopping device, taken in the plane of expansion;

FIG. 13 is a fragmentary sectional view of the upper portion of the collapsed stopping device, taken on the line 1313 of FIG. 9;

FIG. 14 is a fragmentary sectional view of the lower portion of the collapsed stopping device, taken on the line 1414 of FIG. 9;

FIG. 15 is a fragmentary perspective view of the upper frame portion of the stopping device, and

FIG. 16 is an end view of a resilient channel-forming frame link of the stopping device.

In the drawings, 10 designates generally a stopping or plugging device of the invention, and 11 designates a gas main or pipe of circular cross-section in which the stopping device isexpanded to block the flow of gas. A relatively small lateral opening 12 of circular shape is cut in the top portion of the main to permit introduction and removal of thedevice. This lateral opening is substantially smaller in diameter than one-third the inside diameter of the main and is closed after the stopping device is removed, as by the usual screw plug, not shown.

The stopping device comprises a frame structure 13 which in its collapsed condition is elongated and relatively narrow, so as to facilitate insertion through the small lateral opening 12 of the gas main. The opposite sides of the collapsed frame structure are preferably slightly bowed outwardly, but are capable of yielding inwardly to an approximately parallel disposition when the device is inserted into the lateral opening 12. The frame structure 13 is so constructed that the peripheral portions thereof may be forced into a substantially circular shape after insertion of the stopping device into the main, as hereinafter described.

The expansible frame structure 13 includes a pair of spaced upperand lower shackle members 14 and 15 each of U-shaped cross section and each having parallel side cheeks 16, FIG. 15, connected by a rounded and narrowed outer cross portion 17, FIG. 15, the cross portion being of arched shape and having tapered edges 18.- The side cheeks of the upper shackle member are preferably connected by a transversely concave bridge portion 19, and may have one or more inner extensions 20 of reduced width. The lower shackle member 15 is generally similar to the upper shackle member but does not have the bridge portion 19. The frame 13 also includes a pair of telescopically arranged rod members 21 and 22, preferably of generally square cross-section, the upper end portion of the upper rod member 21 being rigidly connected within the upper shackle member 14, as by brazing or welding, and the lower rod member 22 being hollow and similarly rigidly connected to the lower shackle member 15. The rod members 21 and 22, which are confined against relative rotation, thus form a telescopic strut connecting the shackle members. The expansible frame structure 13 further includes a pair of resilient link bars 23 arranged at opposite sides of the telescopic strut 21, 22. Each link bar comprises an elongated rubber body 24 of generally rectangular cross-section having embedded or molded therein at its inner side a longitudinally extending laminated torsion-resisting leaf spring 25 with retaining clips 26. The main or longest spring leaf 27, which is farthest from the inner side of the link bar, projects from the opposite ends of the rubber link body and is provided with curled end eyes 28 extending between the side checks of the shackle members 14 and 15 and secured thereto by pivot-forming cross pins 29. Each shackle member is provided with a pair of the cross pins 29 near opposite ends thereof, and the cross pins of the two shackle members are all parallel to each other and extend at rightangles tothe axis of the telescopic strut. The outer side of each rubber link body is provided with a longitudinally extending parallel-sided channel 30 opening at the opposite ends of the body and having a bottom portion 31 of semi-circular cross-section. The channels 3i) in the two link bodies form seats receiving an inflatable rubber tube 32 which is arranged about the periphery of the frame structure, as hereinafter described.

The inflatable tube 32 has a closed end 33 sealed by a plug 34 and inserted in an end of the lower U-shaped shackle member 15 in which it is secured by a cross pin 35, FIG. 12. From this end the tube extends upwardly 7 into the hollow rod member 22.

'2 along one of the channeled resilient link bars 23, thence through the upper shackle 14, thence downwardly along the other channel link bar 23, hence into the other end of the lower shackle member 15, and thence upwardly The portions of the inflatable tube extending through each of the shackle members 21 and 22 are laterally confined by the cheeks l6 and cross portion 17 of the shackle members. The inflatable tube is further confined by the bridge member 19 of the upper shackle member 14. Adjacent to the lower shackle member 15 a flexible but substantially nonexpansible tube or hose 36 is connected to the inlet end of the inflatable tube by a coupling 37 and extends outwardly through a slot-like lateral opening 38 in the hollow square rod member 22. The other end of the tube or hose 36 is connected to inflation control means hereinafter described.

A rubber diaphragm 39, which in its free condition is of oval domed shape as seen in FIG. 6, is stretched over the stopper frame 13, the marginal portion of the diaphragm having an inturned channel 49 adapted to t over the resilient link bars 23 of the frame and over the shackles 14 and 15. When so stretched the diaphragm becomes narrowed and has substantially parallel opposite sides and a folded or corrugated face portion 41, as seen in FIGS. and 11. The applied diaphragm may be vulcanized in place on the frame or may merely have a tightfrictional fit on the frame. The channeled edge portion of the diaphragm fitting over the shackle members is anchored in place by metal wearresisting shoes 42 and 43 at opposite sides thereof, the shoes being clamped against the diaphragm by screws 44 passing through openings 45 in the diaphragmand threaded into openings 46 in the opposite side walls of the U-shaped shackle members. The side edges and outer edges of the shoes '42 and 43 are thinned; and the outer edges 47 are also curved inwardly and terminate at or near the periphery of the marginal portion 40 of the diaphragm, these inturned edges or the shoes snugly engaging the diaphragm. These shoes, which are formed of brass or other suitable metal, prevent abrasion of the rubber diaphragm when the stopping device is manipulated in the pipe.

The stopping device includes an improved operating mechanism for positioning the diaphragm within the pipe or main '11. This mechanism comprises a manipulating rod or handle 48 of suitable length having a bent lower'end portion disposed between and pivotally connected by a cross pin 49 to a pair of spaced U-strap' cars 50 projecting laterally from the lower shackle member 15, the free end of the handle having a hand-grip loop 51 extending in a vertical plane. The flexible tube or hose 36 extends along the rod 48 and is secured thereto by a clip 52. A second rod 53 has a bent lower end portion disposed between and pivotally connected by 'a cross pin 54 to a pair of spaced ears 55 projecting laterally from the upper shackle member 14, the other end of the rod 53 having a hand-grip loop 56 extending in the plane of the red at right-angles to the plane of the hand-grip S1. A block 57 is slidable along the rod 53 and has a bore 58 receiving the rod therethrough, the block being clamped in adjusted position along the rod bya wing screw 59. A hook rod 60 has a shank portion rigidly secured at one end to the block 57 and projecting toward the pivoted end of the rod and is provided with a downwardly projecting hook or tooth 61 adapted to engage the rim portion of the lateral opening 12 in the pipe or main 11, as seen in FIG. 1. Since the air supply hose 36 is connected to the inflation tube 32 at the lower end portion of the stopping device, this hose will be relatively free from kinking.

The flexible tube or hose 36 is suitably connected to a compressed air bottle or reservoir-forming tank 62 for expanding the stopping device Within the main or pipe. The tank outlet is secured to the lateral branch of a T-fitting 63. Another branch of the T-fitting is connected to a pressure gauge 64, and the third branch of the fitting is connected by an elbow 65 to an end of an elongated valve casing 66 extending downwardly along the tank close to the side of the tank, Laterally offset air passages 67 and 68, FIG. 4, extend longitudinally in the valve casing from opposite ends thereof, the former communicating with the elbow 65 and the latter with the air supply hose 36 through a coupling 69. A springloaded air charging check valve 70 includes a valve nipple 71 which is laterally secured in the valve casing in communication with the passage 67 and has its outer end normally closed by a screw cap '72. A discharge valve 73 controls access of compressed air from the tankto the hose 36 and includes a valve bonnet 74 laterally secured to the valve casing. A needle valve stem 75 with a thumb wheel 76 at its outer end is screw-threaded in the bonnet 74 and normally closes a valve port 77 opening between the casing passages67 and 68. A venting valve'78 controls venting or release of air pressure from the inflation tube of the stopping device and in-- cludes a valve bonnet 7h laterally secured to the valve casing at a point betweerithe discharge valve 73 and the hose coupling 69. A needle valve stem 80 with a thumb wheel 81 is screw-threaded in the bonnet 79 and normally closes a valve port 82 at the inner end of the bonnet extending between the passage 68 and a lateral exhaust port 83 in this bonnet, The hose 36 is of sulficient length so that, if desired, the air tank can be placed at ground level above the gas main trench. However, the tank is sometimes placed in the trench when only a single workman is available.

In the operation of the apparatus, the stopping device it) is initially in the collapsed condition shown in FIGS. 2, 9, and 12, and the charged air'tank 62 has its discharge valve 73 and venting valve 79 inclosed condition. After the lateral hole or aperture 12 has been cut in the gas main, or after a previously cut hole has been unplugged, the collapsed stopping device 10 is inserted through the hole in an inclined rev'e'rs'ely turned position, as seen in FIG. 2, the manipulating rods 48 and 53 being in parallel relation to the longitudinal axis of the stopper frame, and the hand-grip loops 51 and 56 being adjacent to each other. The shoe-protected lower end of the collapsed stopping device is brought into slidable engagement with the lower inner wall of the main, and the inclined stopping device is then turned about.

the axis of the rod 48, bringing the upper and lower ends of the device into engagement with the inner walls of the main, During this maiii'pulation of the stopping device the handle loops 51 and 56 form indicators informing the user as to the orientation of the stopper within the pipe. The hook 61 on the rod '53 is then engaged with the edge of the lateral opening 12 in the main, and th manipulating rod 48 is pulled upwardly to swing the stopper about the fulc'rumforming pin 54 to a nearly vertical position, as seen in FIG. 1,- causing the stopper frame to assume a circular shape, as seen in FIG. 7.

During insertion and positioning of the stopper, the metal wear shoes 42 and 43 thereof slidably engage the pipewalls, facilitating movement of the stopper and minimizing abrasion of the rubber diaphragm. After the expanded stopper-is in its approximately vertical position in the pipe, as seen in FIG, 1, the rubber tube 32 therein I is quickly inflated by opening the discharge valve 73 at the air tank, the peripheral portion of the rubber diaphragm being thus expanded to seal any surfacev irregularities which may be present in the inner 'walls of the pipe. The discharge valve 73 may then be closed. The

portions of the rubber tube 32 within the narrow arched cross portions 17 of the shackle members 14 and 15 do not engage the'pipe, but these cross portions, which are covered by the diaphragm, are of relatively small area and are urged outwardly by the stressed resilient link bars 23 of the expanded stopper frame. In its expanded and inflated condition the stopper is capable of resisting a gas pressure of several p.s.i. With the expanded stopper in place in the gas pipe, the necessary repairs or other operations on the pipe can be effected. Thereafter, the stopper-inflating tube 32 is vented by opening the venting valve 73, whereupon the stopper is swung forwardly to an inclined position by pushing inwardly on the rod 48, permitting the stopper to resume its elongated collapsed condition. The stopper is then turned over to the position shown in FIG. 2 and is withdrawn through the lateral pipe opening 12. The pipe opening 12 then is closed and sealed, as by the usual screw plug, not shown, whereupon normal gas flow through the main or pipe can be restored. The air tank 62 can readily be recharged when necessary by connecting an air supply hose to the check valve nipple 71, the discharge valve 73 and venting valve 78 being then both closed.

It is usually not possible to completely remove the pressure from a gas main when repairs are necessary. However, with the apparatus of the present invention, the stopping or plugging means can be quickly applied to and removed from a gas main with but little loss of gas and in a relatively safe manner.

When the stopping device is in operative position within the pipe, the peripherally expansible diaphragm will not only seal any surface irregularities in the inner walls of the pipe, as above noted, but will also accommodate oversize variations in the inner diameter of the pipe.

I claim:

1. In a flow stopping apparatus for a gas main, an expansible frame structure comprising oppositely disposed shackle members each having an outer cross portion, telescopic strut means connecting said shackle members, a pair of resilient link bars disposed at opposite sides of said strut means and having their opposite ends pivotally connected to said shackle members, said link bars being normally in an approximately straight condition but being bowable outwardly by inward pressure on said shackle members, each link bar having a channel at its outer side extending longitudinally of the bar, an 'air'inflation tube disposed in said'link bar channels and extending in said shackle members under said cross portions, and an elastic diaphragm carried by said frame structure and including portions overlying said tube and said shackle member cross portions, the diaphragm portions overlying said tube being urged outwardly by said tube upon inflation of said tube for sealing engagement with the inner walls of a gas main, and the diaphragm portions overlying said shackle member cross portions being urged outwardly by the flexural stress on said resilient link bars when said bars are bowed outwardly.

2. In a flow stopping apparatus for a gas main, an expansible frame structure comprising oppositely disposed shackle members each having opposite side walls and an arched cross portion connecting said side walls, said cross portion being narrower than said side walls, telescopic strut means connecting said shackle members, resilient link bars disposed at opposite sides of said strut means and having their opposite ends pivotally connected to said shackle members, said link bars being bowable outwardly and being longitudinally channeled at their outer sides, inflation tube means extending in said channeled link bars and through said shackle members, and an elastic diaphragm carried by said frame structure and having peripheral portions overlying said link bars and shackle members, said tube means, upon inflation, urging the overlying diaphragm portions into sealing engagement with the inner walls of a gas main.

3. In a flow stopping apparatus for a gas main, an expansible frame structure comprising oppositely disposed shackle members each having opposite side walls, telescopic strut means connecting said shackle members, a

pair of resilient link bars disposed at opposite sides of said strut means and having their opposite ends pivotally connected to said shackle members, said link bars being bowable outwardly by inward pressure on said shackle members, each link bar having a channel at its outer side extending longitudinally of the bar, inflation tube means extending in said link bar channels and shackle members, an elastic diaphragm carried by said frame structure and including portions overlying said tube means to be urged outwardly by said tube means upon inflation of said tube means for sealing engagement with the inner walls of a gas main, said diaphragm further including opposite side walls adjacent to its peripheral portion engaging the opposite side walls of said shackle members, metal plates engaging said opposite side walls of the diaphragm adjacent to said shackle members, and means for securing said plates to said shackle members, the outer edges of said plates being adjacent to the periphery of said diaphragm.

4. In a flow stopping apparatus for a gas main, an expansible frame structure comprising oppositely disposed upper and lower shackle members, telescopic strut means connecting said shackle members, a pair of resilient link bars disposed at opposite sides of said strut means and pivotally connected at opposite ends to said shackle members, said link bars being longitudinally channeled at their outer sides and being bowable outwardly by inward pres sure on said shackle members, an inflation tube looped around said frame structure and extending in said longi= tudinally channeled link bars, said tube having a closed end secured to said lower shackle member and an inlet end extending upwardly from said lower shackle mem her, an elastic diaphragm carried by said frame structure and having a peripheral portion expansible by said infiation tube upon inflation of said tube, a first manipulat ing rod pivotally secured to the lower portion of said frame structure and swingable inwardly towards said frame structure to lie approximately parallel to said strut means, a second rod pivotally secured to the upper portion of said frame structure, the pivotal axes of said rods being substantially parallel, said second rod having a hookportion adapted to engage an edge of a lateral in sertion opening formed in a gas main, and an air supply hose connected to the inlet of said inflation tube and ex tending along said first rod.

5. In a flow stopping apparatus fora gas main, a stop per assembly including an elongated articulated frame structure including oppositely disposed shackle members at the ends thereof, telescopic strut means connecting said shackle members, a pair of resilient link bars disposed at opposite sides of said strut means and pivotally connected to said shackle members, said link bars being longitudi nally channeled at their outer sides and being outwardly bowable, an inflation tube extending in said longitudinally channeled link bars, and an elastic diaphragm carried by said frame structure and having a peripheral portion surrounding said structure, said diaphragm adapted to be expanded by said tube, upon inflation of said tube, into engagement with the inner surface of a gas main, said diaphragm in its free condition being of domed oval shape and having its peripheral portion in the form of an inwardly opening channel adapted to embrace said frame, the length of the free diaphragm being less than the length of the articulated frame in the elongated condition of said frame, and the width of the free diaphragm being greater than the width of the articulated frame in its elongated condition.

References Cited in the file of this patent UNITED STATES PATENTS Ankarlo Aug. 24, 1943 

